A temporary restraining order issued last month by a Cook County Circuit Court judge over the county's planned penny-per-ounce tax on sweetened beverages was upheld Monday by an Illinois appellate court.

The Illinois Retail Merchants Association, which filed the lawsuit against the county, said it appreciated the 1st District Appellate Court's decision to uphold the temporary restraining order. It believes that the tax violates the uniformity clause of the Illinois Constitution.

"We are now asking for the lower court to rule on a preliminary injunction that will continue the status quo until we have a final decision on the legality of the ordinance," Rob Karr, the association's chief executive, said in a statement.

A hearing on the preliminary injunction is scheduled for Wednesday.

"We respect the appellate court decision and will prepare to move forward at the trial court level," said Frank Shuftan, spokesman for Cook County Board President Toni Preckwinkle.